ipanat: Add support for Multi PDN

IPAv4 HW presents new Multi PDN with NAT functionality.
This change adds SW support of this feature.

Change-Id: I25ff6a52261fad60ecea4be044b0e15ba55821f5
diff --git a/configure.ac b/configure.ac
index 33164c0..6662ef6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -24,6 +24,7 @@
       AS_HELP_STRING([--with-sanitized-headers=DIR],
          [Specify the location of the sanitized Linux headers]),
       [CPPFLAGS="$CPPFLAGS -idirafter $withval"])
+AM_CONDITIONAL(KERNELMODULES, [test -n -eq 0])
 
 AC_ARG_WITH([glib],
       AC_HELP_STRING([--with-glib],